1 . 某高校为了提升学校餐厅的服务水平, 组织4000名师生对学校餐厅满意度进行评分 调查,按照分层抽样方法,抽取200位师生的评分(满分100 分)作为样本,绘制如图所示的 频率分布直方图,并将分数从低到高分为四个等级:
的值,并估计满意度评分的
分位数;
(2)若样本中男性师生比为
,且男教师评分为80分 以上的概率为0.8, 男学生评分为80分以上的概率0.55, 现 从男性师生中随机抽取一人, 其评分为80分以上的概率为多少?
(3)设在样本中,学生、教师的人数分别为
,记所有学生的评 分为
,其平均数为
,方差为
,所有教师的评分为
,其平均数为
,方差为
,总样本的平均数为
,方差为
,若
,试求
的最小值.
满意度评分 |
| |||
满意度等级 | 不满意 | 基本满意 | 满意 | 非常满意 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/267c88e52743f3dedd4e60569cb958fe.png)
(2)若样本中男性师生比为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa9c934d84feba963335cc7edf01610e.png)
(3)设在样本中,学生、教师的人数分别为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb785c57f06f8e0051e49a5f1b43fde1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1402b0375d6babc0b979a368d1fbb54e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfbe7f95b5d89f9409ec24536da9e826.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a63cadbf6b0d54955a3c3d1b7a62b14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35ba484662ddaac29c2c44ed136f79c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb525270c748eddaaecc4a549cca250e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9289410bd35c9d57326b93cc7f4c4767.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d41042207515dd2e8349c805e6aee400.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/671f43c79d612c93a6d160335e86e177.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d954d1e6b433661e694eddc231be784.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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2024高三下·全国·专题练习
2 . 若
,则
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/173e4fda9f3ad2244f68c6e98dd6588d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe452ba1779be66f74e548cd327c2f68.png)
A.![]() | B.![]() | C.253 | D.126 |
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名校
解题方法
3 . 已知函数
,若存在实数
.满足
,且
,则
的取值范围是_____
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63f0765298b308999e04b74ecb6b579a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8ccd22fd0ca1a8e1468329284f91b6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3604274ad6707a906eba371a9e884144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/373a065bb69b411e5107f05d8cb13573.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fc7d6393821d46bcaca5c39b6f5bcb8.png)
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名校
解题方法
4 . 已知
,
是函数
的零点,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f9c1f914da4657eca7865982b130b299.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d75442a901f013aeb5c52a7113ae9b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c487295d441397ea078d433e61087cec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67a91d7fa3be7708a277b8a836c5af89.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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5 . 数列
的前n项和为
,若数列
与函数
满足:①
的定义域为
;②数列
与函数
均单调增;③存在正整数
,使
成立,则称数列
与函数
具有“单调偶遇关系”.给出下列两个命题:( )
①与数列
具有“单调偶遇关系”的函数有有限个;
②与数列
具有“单调偶遇关系”的函数有无数个.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fd70bc89bcebe10b16931b1e654d211.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
①与数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e439697572e2dbd6826f7743b969813.png)
②与数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a97e99f49ad1998d2858e1963aa45de.png)
A.①②都是真命题 | B.①是真命题,②是假命题 |
C.①是假命题,②是真命题 | D.①②都是假命题 |
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名校
6 . 采矿、采石或取土时,常用炸药包进行爆破,部分爆破呈圆锥漏斗形状(如图),已知圆锥的母线长是炸药包的爆破半径R,若要使爆破体积最大,则炸药包埋的深度为___________
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解题方法
7 . 已知
为坐标原点,曲线
在点
处的切线与曲线
在点
处的切线平行,且两切线间的距离为
,其中
.
(1)求实数
的值;
(2)若点
分别在曲线
上,求
与
之和的最大值;
(3)若点
在曲线
上,点
在曲线
上,四边形
为正方形,其面积为
,证明: ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/634eecef5979fe32878d032e9736bcad.png)
附:ln2 ≈ 0.693.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/325cb5d7a2edc99c9bfcf39e6ffc7c5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/248b75c2ba3d6f870b1a7255e652b8b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b037b9629c12214eb24d990fc9855852.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/addc3241a83f4b61d46402319b7f1da1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c90e8d5d7fed033f48270b1ff825fcd5.png)
(1)求实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62ff2912fd8d93b6e692936d95b727c5.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f44755c5fee4b90266eac73ad47a128.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32595168b1cc7fd374aeb8d833c1cbb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/579d861f3f214342af735e6f0a8db139.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d3ea1f0e09c8f73a18a08f14188f264.png)
(3)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ae6f48b9a53c0155a692509cf31f7e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5aa69fd8445d01c98634c2e885b47d5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/634eecef5979fe32878d032e9736bcad.png)
附:ln2 ≈ 0.693.
您最近一年使用:0次
名校
8 . 如下图,四棱锥
的体积为
,底面
为等腰梯形,
,
,
,
,
,
是垂足,平面
平面
.
;
(2)若
,
分别为
,
的中点,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5acb763021bf166ca719d07223591d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/279e119eed905cf15026649a1b86502a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a398397362a18da1cc9f24bf3f356ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f29c3e772e56008790298824122792.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7713c13736076f1fe2c139bb4a4b6d6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9104a1941e557a85fd1496bc2b9be297.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99ab98efd2b5fcbfeae61fe37f921a0e.png)
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9 . 如图,在三棱锥
中,已知
,
,
,
,
,
.
为
的中点,求证:
;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41e5db1d2fd912f77923e4c120a7dc19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080ca48cd27d4bf9d9ef084b558fc17a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ce64044898d0460aac161d93a455304.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba8c340f8945083d2993ff28eabfcccf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4d6b27a35a18492e60b5b99789d3395.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c177e06cc3f703e8ca7be7c491fa2942.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cc6f6dfdbe7d39891c35f67e1a95c7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21665d21bbfb04410c78345de1fd15ae.png)
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10 . 已知抛物线
的焦点为
,
为坐标原点,倾斜角为
的直线
过点
且与
交于
,
两点,若
的面积为
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64447af8454c613a58b11d9274d3da2c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25dd698d57d1cf239eb8752aecaaa4f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adbd3e8cf8325999cde03adf845d3dd0.png)
A.![]() |
B.![]() |
C.以![]() ![]() |
D.![]() ![]() |
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